1. Field of the Invention
The present invention relates generally to stents, stent loading stent contracting and stent delivery systems and their respective methods of use. Some embodiments of the invention are more specifically directed to a removable protective sheath which protects the stent from direct contact with a stent loading and/or stent contracting system. Some embodiments are more specifically directed to stent loading, contracting and/or delivery systems which are configured to accommodate such a protective sleeve and stent.
2. Description of Related Art
A stent is a generally tubular device that is used to support a bodily lumen. A stent is typically delivered to a desired bodily location via a catheter. Often the stent is loaded onto a portion of the catheter, such as a balloon or other region of the catheter shaft. In some stent delivery systems the stent is crimped to the catheter in order to minimize the profile of the stent on the catheter and to prevent undesired movement of the stent relative to the catheter shaft.
A number of techniques for loading and contracting a stent to a catheter shaft or balloon are used. One such technique that is commonly used in the radiological suite involves hand crimping the stent to the balloon. A stent is placed over an uninflated balloon and then squeezed with the fingers until the stent is in intimate contact with the uninflated balloon. The technique is highly operator dependent and can affect stent profile and stent placement with respect to the balloon and radiopaque markers. It can also affect the dilatation length of the stent and lead to pinching of the balloon.
Other techniques for crimping stents involve the use of mechanical devices for crimping stents. Mechanical stent crimpers have been disclosed in a number of patents including U.S. Pat. Nos. 6,387,118; 6,108,886; 6,092,273; 6,082,990; 6,074,381; 6,063,102 and 5,992,000. Mechanical stent crimpers have also been disclosed in a number of copending, commonly assigned patent applications including U.S. application Ser. No. 09/401,467 now U.S. Pat. No. 6,352,547, Ser. No. 09/401,213 now U.S. Pat. No. 6,387,117, Ser. No. 09/404,986 now U.S. Pat. No. 6,769,161, and Ser. No. 09/401,218 now U.S. Pat. No. 6,360,577.
When assembling a catheter for delivery of a stent and for insertion into a body vessel, the stent is loaded onto the catheter. During the loading process the catheter and in some cases the stent is manipulated, often by hand. The manipulation of the catheter may cause the stent to be contacted and potentially damaged. Where the stent includes or is coated with a drug or other material, such contact may disturb the coating and impair the proper delivery thereof. In addition, contacting the stent during the loading and/or crimping process may result in the drug coating of the stent being contaminated with the residue of previous stent coatings that have been previously contacted by the loading and/or crimping system.
Thus, there remains a need to provide a device or mechanism for preventing direct contact between a stent, particularly a drug coated stent, and the tool or system used to load and/or crimp the stent onto the catheter shaft or balloon.
All US patents, applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.